DARC “Logic Method” for Molal Volume Prediction

Solvation Parameters. 2. A Simplified Molecular Topology to Generate Easily Optimized Values

“…In brief, the principle of this method is to consider a given atom of the molecule, called a focus, as a starting point for generating progressively a chemical graph environment in concentric layers. The DARC system was further applied to structure−activity relationships in physical chemistry (Dubois et al , ). The difficulty with the DARC system in this later field is that the possible number of parameters (independent variables) for a wide category of substances is so high that the method must be limited to narrow families of compounds.…”

“…The difficulty with the DARC system in this later field is that the possible number of parameters (independent variables) for a wide category of substances is so high that the method must be limited to narrow families of compounds. For example, in the case of the prediction of molar volumes at 25 °C, topological learning using 300 aliphatic alkanes in the range of carbon atoms C6-C11 is only applicable to this type of compound (Dubois et al 9 ). In opposition of this very precise topology, a very simple technique is to assign an increment to each type of atom (carbon, hydrogen, oxygen, etc.…”

A General Guidebook for the Theoretical Prediction of Physicochemical Properties of Chemicals for Regulatory Purposes

“…• The simple method of Abraham et al 366 for the calculation of characteristic volume, which is closely correlated with molar volume. • The method of Dubois and Loukianoff 367 for the prediction of relative density of alkanes. • Finally, the most recent version of the GC method 21 with CI (called GC+) was used to model liquid molar volume for 1056 molecules with an R 2 of 0.997 and an AAD of 2.03%.…”

“…There are several group contribution methods available in the literature for the prediction of the relative density. The following is a nonexhaustive list: The method of Girolami et al for organic, inorganic, and metal−organic liquids (with an R 2 = 0.982). The method of Grain et al based on the T b and molecular mass of organic compounds. The GCVOL method proposed by Elbro et al (which is based on the van Krevelen approach) for the prediction of liquid densities of solvents, oligomers, and polymers as a function of the temperature. The simple method of Abraham et al for the calculation of characteristic volume, which is closely correlated with molar volume. The method of Dubois and Loukianoff for the prediction of relative density of alkanes. Finally, the most recent version of the GC method with CI (called GC+) was used to model liquid molar volume for 1056 molecules with an R 2 of 0.997 and an AAD of 2.03%. …”